The anterior commissure of the larynx.

This study is based on a very large series of histological sections of non-tumour-bearing larynges, most of them in the horizontal plane. Six hundred sections in one larynx were performed to show the constitution of the anterior region of the larynx at all levels. Although the same tissues are present (fibres, glands and vessels) in almost the entire extent of the anterior segment of the larynx, there is a small zone immediately above the vocal cords with neither glands nor vessels. The authors designate this zone as 'plane O' which separates the anterior commissure from the thyro-epiglottic ligament. It is not possible to separate the anterior commissure from the most anterior portion of the subglottis, because the glands and vessels are in continuity. There are 2 regions of the anterior part of the larynx: a supraglottic (vestibulo-epiglottic) and a glottic-subglottic to which the anterior commissure belongs.